Hydraulic hold open mechanism for hinged members



R. w. VOSE 2,948,915

HYDRAULIC now OPEN MECHANISM FOR amass MEMBERS Aug. 16, 1960 2Sheets-Sheet 1 Filed July 15, 1957 g "wav 0 7 4 it: u n 4 C/A/ u W 0/ INrw/ i m Q m w Q Aug, 16, 1960 R. w. VosE 2,943,915

HYDRAULIC HOLD OPEN MECHANISM FOR HINGED MEMBERS Filed July'15, 1957 2sne' 'ts-sneet 2 INVEN TOR. Ru hart .LU .Vuse

ATTORNE x5 0% x v MFQ Unit HYDRAULIC HOLD OPEN MECHANISM FOR HINGEDMEMBERS Filed July 15, 1957, Ser. No. 672,031

Claims. (Cl. 16-82) This invention relates to a hydraulic hold-opendevice for hinged members and has for a general object to provide meansfor holding a hinged member from move ment in one direction of travelagainst pressures under a predetermined value and to permit movementthereof at greatly reduced pressures once said predetermined pressure isapplied to commence movement of said hinged member in the desireddirection.

The invention will be described in connection with its utility as auniversal door holder and specifically with respect to a hold-opendevice for automobile doors although it will be readily understood thatthe structure could easily be used in a great variety of other specificapplications. By the term universal is meant the action of the device inautomatically holding the door against movement in one direction at anyposition to which the hinged member, as a door, may be moved. In otherwords an automobile door may automatically be held against closingmovement in any open position desired.

Other objects and advantages are to provide a device in which openingmovement of a door may be accomplished without any positive restraint inorder to place the door at a desired position in which the restraintagainst initial closing movement of a door may be calibrated at apredetermined value and thereafter closing motion continued in anessentially unimpeded manner; in which interruption of the closingmotion of a door will automatically result in reestablishing a hold-openaction at the point of interruption and in all positions except when thedoor is closely adjacent its closed condition; in which the release of adoor from an open position will be smoothly I t cs atei ir accomplishedwithout any jerky motion and during which a metered decreasingresistance will take place for smooth closing action; and in which boththe opening and closing movements of a door may, however, be madesufliciently restrictive so as to check excessive opening rates, as forexample, when a door may be blown open by a strong wind and to checkexcessive closing rates as when forces might be applied to otherwiseslam a door towards its shut position.

These and other specific objects and advantages will be understood fromthe following disclosure of an embodiment of the invention and thenovelty thereof pointed out in the appended claims.

In the drawings,

Fig. l is a representation of the hinged mounting of an automobile doorwith the device of this invention mounted thereon;

Fig. 2 is a longitudinal sectional View of the device shown in Fig. 1;

Fig. 3 is an exploded view in perspective showing the parts of thepiston assembly shown in Fig. 2; and

Figs. 4 and 5 are fragmentary Views on an enlarged scale showing detailsof construction.

Referring to the drawings Fig. 1 represents an automobile door 2supported for hinged movement about a body frame pillar 4 on hinges suchas the one shown at 6. Hinge 6 is of a conventional design forautomobile doors and comprises a box type hinge member 5 fixed to thepillar 4 and on which the usual goose neck 7 is pivoted for hingingmovement of the door 2 to which it is attached. Motion of the door 2 onhinge 6 is controlled by the hydraulic mechanism at 8. A cylinder 9 ispivotally attached to the door 2 by a mounting bracket 10 and a pistonrod 12 is attached to the body pillar portion 4 by a bracket 14. v

The device 8 functions to permit opening movement of the door to a fullyopen position as shown in phantom in Fig. 1, and to do so in anessentially unimpeded manner. It is, however, arranged to hold the dooropen against pressures below a certain value tending to swing it in aclosing direction and at any position to which it may be moved betweenthe fully open and the closed position. In the case of an automobiledoor, and as specifically disclosed herein, the mechanism is preferablydesigned so that when near the extreme closed position means areprovided to prevent a holding action so as to permit latching the door 2without interference. The device is designed to resist such closingmovements from any open position in the absence of a predeterminedforceapplied to close the door, but once the initial hold of the device isbroken continued closing motion may be accomplished at greatly reducedpressures. In the event closing movement ceases before the door is shutthe device will automatically operate to again impose a hold open actionin which the initial closing force must be applied before furthermovement can again proceed.

In the sectional View of the cylinder 9 (Fig. 2) a piston 15 is shownattached to the inner end of the piston rod 12. Cylinder 9 is filledwith suitable hydraulic fluid, such as a low Viscosity oil, and issealed at the end opposite the piston rod 12. Piston 15 is cup-shapedand the cylindrical outer wall thereof is annularly spaced from theinner wall of the cylinder to form a passage therebetween. Adjacent therod end of the piston in the base section of the cup an annular groove18 is formed in which an O-ring seal 16 is positioned. Groove 18 isprovided, as shown, with a shallow portion toward the rod end of thepiston and, as will be appreciated, is adapted to force the seal 16outwardly into sealing contact with the cylinder 9 in the normal mannerwhen pressure is exerted on the fluid at the right side of piston 15.Seal 16, however, will ride free without sealing when pressureis exertedon fluid in the cylinder at the left side of piston 15. To fully insureagainst any chance sealing action in the latter case, severalcircumferentially spaced longitudinal grooves or passages 20 are formedin the wall of the piston for passage of fluid from the deeper end ofthe groove 13 as will be readily seen from Fig. 4. A check valvedpassage means is thus provided for free flow of fluid from the left handside of the piston to the right hand side thereof and for sealingagainst a reverse flow of fluid through the same. Thus the piston canreadily be moved towards the rod end of the cylinder in an essentiallyunimpeded fashion as for opening movement of the door shown in Fig. 1.

Movement of piston 15 by flow through the annular passage betweencylinder and piston for closing movement of a door, as toward the righthand end of the cylinder, is thus blocked. For such reverse flow fromthe right to the left hand end of the cylinder a second valve means isprovided. Yieldable pressure receiving means of this latter Valve serveto impart the hold-open action desired. In the absence of pressuresabove a certain predetermined value in the cylinder on the right handside of the piston a hinged door will not swing towards its closedposition. If a closing force is exerted on the door of sutficientmagnitude to generate a pressure on the right side of the piston of avalue greater than the predetermined value the door will close.

I As shown, a plate 40 is permanently fixed 1n the open end of thecup-shaped wall of piston to form an interior cylindrical chamber 4-1.Plate 40 is provided with a central inlet opening 39 having an inturnedlip as best shown by Fig. 5. The opening is of a restricted area as willbe descirbed and within the chamber 41 is a movable valve disk 26 fixedon a supporting rod 28. The rod and disk are longitudinally movable inthe cylinder 41 with passage for fluid past the disk afforded by anannular spaced relation between the edge of the disk and the chamberwall. As will be noted, piston rod 12, slidably extending through theend wall of cylinder 9 with a sealing ring at 43, is threaded into thebase of the cup-shaped piston 15 on the axis thereof. This attached endportion of rod 12 is formed with an elongated socket 27 in the blind endof which is positioned a compression spring 36. Seated against spring 36is the end of supporting rod 28 which is telescopically received insocket 27. Rod 28 extends axially at its other end beyond the valve disk26 and through central opening 39 of plate 40. Against the face of thevalve disk 26 and on rod 28 is a washer or collar 34 adapted for seatingagainst plate 40 to close off central opening 39 in the closed positionof the valve. Outwardly of the collar the stem of rod 28 is formed witha tapering reduced portion 30 and a reduced tip portion 32 as will bedescribed.

Outlet passages 46 at annularly spaced intervals in the base portion ofthe piston 15 are provided for free flow of fluid from the chamber 41 tothe rod end of the cylinder. It will also be noted that the cylindricalchamber 41 is formed with an enlarged end section as at 44.

It will also be seen from Fig. 2 that the valve disk 26 and itssupporting stern assembly (which acts as an auxiliary piston valve) isurged by spring 36 to a seated position against plate 40. The centralopening is thus closed by collar 34 and rod 28. In the absence of anyfluid pressures at the right hand end of the cylinder the opening 38remains closed. When the fluid at this end is under pressure by urgingthe piston 15 to the right, pressure will be exerted against the annulararea of the collar blocking opening 39. This area is, of course, but avery small fractional portion of the area subject to fluid pressures atthat end of the piston. Accordingly spring 36 is calibrated to requirefluid pressures of a certain value at the right hand end of the cylinderin order to unseat the collar 34 and initiate a closing movement. Oncefluid begins to flow through opening 39 it will be appreciated thepressure thereof will be transmitted also against the active face of thedisk 26. Since the area of the face 25 receiving such pressures is equalto a substantial fractional portion of the area of piston 15 receivingsuch pressures, greatly reduced fluid pressures will serve to maintainthe valve unseated against the urging of spring 36. Thus, once the valveis broken by initial forces of a predetermined value tending to movepiston 15 toward the right hand end of the cylinder, continuing movementof the piston and reverse flow of fluid may be accomplished by applyingsubstantially lesser pressures to overcome spring 36.

It will be noted movement of piston 15 toward the right hand end of thecylinder moves the inner end portion of rod 12 into the interior of thecylinder. Accordingly an expansion chamber 42, provided with a springloaded disk 45 and in communication with the rod end of the cylinder,receives the fluid displaced by rod 12.

In order to prevent a sudden release of pressures and a consequent jerkymotion of the hinged member being moved when the pressures are raisedsufliciently to break open the valve, the metering stem portion of rod28 serves to control the admission of fluid to the active or pressurereceiving face of valve disk 26. The proportions of the metering stem 30and its fit inside the opening 39 of plate 40 are such that anappreciable motion of a door occurs (and at a gradually decreasingresistance) before the valve disk reaches the full extent of its strokeand is positioned in the enlarged section 44 to permit the relativelyunrestricted flow through the enlarged section and through passages 46.

It may \also be noted that, as in the case of the automobile door 2, thepiston, when the door nears a closed position, will be in closeproximity to the end of cylinder 9 and the release stern portion 32 ofthe rod 28 may contact the end wall of the cylinder (see Fig. 5). Valvedisk 26 will thus be mechanically held in open position to prevent theholding action which would otherwise occur. In an automobile door thiswill permit latching the door without impediment where closing movementof the door may be interrupted near the closed position.

While passages 20 and the clearance between piston 15 and the wall ofcylinder 9 may be so sized that relatively free fiow of fluid may occurat normal rates of opening a door, they may also be made sufllcient lyrestrictive to somewhat check excessive opening movement. This might bedesirable in a case where the door could be blown open by a strong wind.Correspondingly, passages such as the plate opening 39, the enlargedchamber portion 44, and passages 46 may be of a size to impede theotherwise possible slamming of a door to shut position.

Having thus described the invention, what I claim as novel and desire tosecure by Letters Patent of the United States is:

l. Hydraulic mechanism for permitting movement of a hinged member in agiven direction only when hydraulic pressure within said mechanismexceeds a predetermined value and comprising a piston rod for attachmentto one of a pair of hinged members, a fluid filled cylinder slidablyreceiving in one end thereof said rod and attachable to the othermember, a piston fixed to the rod and slidable in said cylinder, checkvalved passage means associated therewith for permitting flow of fluidin one direction from a first side of the piston to an opposite secondside and preventing reverse flow in the opposite direction, secondvalved passage means associated with said piston for permitting saidreverse flow of fluid including a valve having means yieldably urgingthe same to prevent said reverse flow until pressure of saidpredetermined value is impressed on fluid in said second side of thepiston to automatically open said valve, and means responsive to fluidpressures in said second side substantially below said predeterminedvalue, once said valve is unseated, for maintaining said yieldably urgedmeans ineffective and permitting continued movement of said hingedmember in said given direction once it has been started.

2. Hydraulic mechanism for permitting movement of a hinged member inagiven direction only when hydraulic pressure within said mechanismexceeds a predetermined value and comprising a piston rod for attachmentto one of a pair of hinged members, a fluid filled cylinder slidablyreceiving in one end thereof said rod and attachable to the othermember, a piston fixed to the rod and slidable in said cylinder, checkvalved passage means associated therewith for permitting flow of fluidin one direction from a first side of the piston to an. opposite secondside, second valved passage means associated with said piston for thereverse flow of fluid from the second to the first side of said piston,said latter means including a chamber having an outlet for freecommunication with said first side of the piston and a valved inletopening communicating with said second side thereof, a valve movable insaid chamber to open and close said inlet opening, the area of saidvalve blocking said opening when in closed position being a smallfractional portion of theentire area of said piston exposed to fluidpressures at said second side thereof, fluid pressures developed in saidsecond side by movement of said piston tending to move said valve awayfrom said closed position and said valve when unseated having a surfacearea equal to a substantial portion of said aforementioned entireexposed area of the piston, said surface area disposed to be acted on byfluid pressures to keep said valve open and yieldable means normallyurging said valve to closed position, said yieldable means beingcalibrated to resist initial valve opening fluid pressures below apredetermined value on said second side of the piston whereby saidyieldable means will be ineffective to seat said valve at substantiallylower fluid pressures once said valve has been unseated.

3. Hydraulic mechanism as in claim 2 in which the exterior wall of saidpiston is spaced from the interior wall of the cylinder to form saidfirst-named passage means and a check valve is provided therefor by anannu'lar groove formed in the wall of the piston and a sealing ringriding in said groove, said groove having a shallow portion at the sidefacing said first side of the piston to force said ring against thecylinder wall in the presence of fluid pressures at said second side ofthe piston.

4. Hydraulic mechanism as in claim 2 in which said valve for said secondpassage means is in the form of a piston having a pressure receivingface opposed to said inlet opening and being movable in said chamber,said piston valve being carried by a supporting rod extending at one endthrough the wall of said chamber opposite said inlet opening and at itsother end through the inlet opening.

5. Hydraulic mechanism as in claim 4 in which said supporting rodextension through said inlet opening is of a reduced taperedconformation for controlled metering of fluid through said opening tothe pressure receiving face of said valve on unseating said valve.

6. Hydraulic mechanism as in claim 4 in which said movable piston valveand chamber are cylindrical with the valve being of a lesser diameterthan the interior diameter of the chamber, and a collar surrounding saidrod extension of the inlet opening for positioning against the pressurereceiving face of the valve, said collar seating against the inletopening in closed position of the valve, and, with said extension,closing off the same.

7. Hydraulic mechanism as in claim 4 in which said piston rod isattached to the wall of said chamber opposite the inlet opening and saidvalve piston supporting rod is telescopically received in a socket inthe attached end of the piston rod, said yieldable means comprising aspring seated in said socket and bearing against the socketed end ofsaid supporting rod.

8. Hydraulic mechanism for permitting movement of a hinged member in agiven direction only when hydraulic pressure with said mechanism exceedsa predetermined value comprising a fluid filled cylinder attachable toone of a pair of hinged members, a piston slidable therein with a pistonrod extending from the cylinder for connection to the other hingedmember, said piston having a cup-shaped wall in annularly spacedrelation to the cylinder Wall with an annular groove cut therein havinga shallow portion toward the base of the cup and an expandable sealingring positioned in said groove for closing the annular passage betweenpiston and cylinder on application of pressure at the open end side ofthe cup, a plate fixed across the open end of the cup having a centralopening therethrough and forming a cylindrical 6 l chamber in theinterior of the piston, an auxiliary piston valve disk in said chamberwith the periphery thereof spaced from said chamber wall, said pistonrod being fixed to said piston axially of the base thereof and having asocketed end portion with a valve supporting rod telescopically receivedtherein and extending through the base of the cup, a spring seated insaid socket urging said supporting rod toward the open end of the cupwith said auxiliary piston valve fixed thereon, said supporting rodfurther extending through said plate opening with a collar fixed thereonengageable against the plate to close oflf said opening when urgedthereagainst by spring, said rod beyond said collar having a taperingreduced end for metered control of fluid passing through the openingwhen the valve is urged away from said plate, said base of the pistonhaving openings for free passage of fluid from the interior chamberthereof to the rod end of the cylinder, and an expansion chamber incommunication with said rod end of the cylinder, the aforesaid springbeing calibrated to resist hydraulic pressures under a predeterminedvalue in the end of the cylinder opposite the rod end as applied throughsaid restricted plate opening against said collar and to yield togreatly reduced pressures as applied against the face of said valve diskwhen said collar is unseated and fluid is passing through said plateopening.

9. The structure of claim 8 in which said tapered end of the supportingrod for the valve disk is engageable against the end of the cylinderwhen said piston is moved adjacent one limit of hinging movement, saidspring for the valve disk thereby being rendered ineflective to closesaid opening,

10. Hydraulic mechanism for preventing movement of a hinged member in agiven direction unless said member is urged in said given direction witha force sufficient to generate an hydraulic pressure within saidmechanism which exceeds a predetermined value, said mechanism comprisinga movable piston and fluid filled cylinder, a rod fixed to the pistonand slidable in said cylinder and attachable to one of a pair of hingedmembers with the cylinder connected to the other member, first valvemeans for permitting movement of said piston for relative movement ofsaid hinged members in one direction and preventing movement of saidpiston in the opposite direction, a second valve means actuated by fluidpressure in said cylinder for enabling said piston to be moved in saidopposite direction and including means for yieldably resisting actuationof said second valve means until said fluid pressure exceeds saidpredetermined value and means responsive to fluid pressuressubstantially lower than said predetermined value for maintaining saidsecond valve in an actuated condition.

References Cited in the file of this patent UNITED STATES PATENTS1,239,510 Nordquist Sept. 11, 1917 2,119,625 Hasuo June 7, 19382,624,566 Caramelli J an. 6, 1953 FOREIGN PATENTS 1,074,257 France Mar.31, 1954

